Steady population:
The relative proportion of various age groups in population is called the age structure. It determine the reproductive status of a population.
The three major age groups are:-
a. Pre - reproductive group ( 0 to 14 years)
b. Reproductive group (15 to 59 years)
c. Post - reproductive group ( age 60 years and above)
The age structure determines the trend of the population. A population is said to be steady, when it has same number of pre - reproductive and post - reproductive age groups. It is a stable population.
